Caps and diaphragms

Caps and diaphragms are dome shaped and fit inside a woman's vagina. They work by stopping the sperm entering the womb. They need to be used with a spermicide. Spermicide is a gel which kills sperm.

Caps and diaphragms are made of flexible rubber or silicone and must be fitted before sex and remain in place for at least 6 hours afterwards. If used properly with spermicide, they can be between 92% and 96% effective at preventing pregnancy. They may protect you against some Sexually Transmitted Infections (STIs).

They come in different sizes and will be fitted to suit you. Because of this a doctor or nurse must fit a cap or diaphragm before using one for the first time. Once you have the right size for you, you use it by putting the spermicide on the diaphragm or cap, then you place it inside the vagina to cover the cervix. You can do this up to three hours before you have sex. If you put it in place before then you will need to add more spermicide and if you have sex more than once, each time you will need to use more spermicide.

Where to get caps and diaphragms

You will need to see a doctor or nurse to find out if a cap or diaphragms is suitable for you and if it is to get it fitted for the first time. Some women are allergic to rubber or spermicide if that’s the case this won’t be suitable for you but the doctor or nurse can advise. You can do this by visiting your GP or Contraception and Sexual Health (CaSH) clinic.